Leatherjacket grubs can destroy your lawn!

Leatherjackets are one of the most devastating lawn pests found in the UK, literally eating their way through an entire lawn. A severe leatherjacket attack will mean that your lawn has to be entirely replaced … which could cost thousands! Read on to learn how to spot them and how to deal with these potentially troublesome pests if you spot them in your lawn.

What are leatherjackets?

Leatherjacket grubs are the larval stage of a species of crane fly called tipula oleracea, which is commonly known as the daddy-long-legs.

These curious, clumsy insects are often seen flying around our gardens in late summer and early autumn, bumbling along the ground, getting trapped behind glass windows and flying into our faces when we least expect it!

Unfortunately for them, their lives are very short as adults, with their only aim being to find a mate and lay their eggs for the next generation. They don’t even have any mouth-parts to eat food, so pose no threat to veg or plants. As soon as their energy has been expended, often in less than a day, they expire.

If they are lucky enough to find a mate, the females will fly low to the ground and lay her eggs in the soil (or your lawn), starting the crane fly cycle again.

Just a few weeks later the eggs will hatch into the infamous leatherjacket grub, which will quickly begin to feast on the roots of the plants found around them. They then reduce their activity in the winter due to the cold, but start up again in the spring, voraciously eating their way through the roots in the soil, killing any smaller plants, such as the humble grass plant.

How can you spot leatherjacket grubs in your lawn?

A selection of leatherjacket grubs

Finding out if you have a leatherjacket infection in your lawn is quite simple and you only need a small pocket knife and good knees!

Firstly, have a general look at the lawn and see if you see any patches of obviously dead grass that seem rather out of place and randomly distributed. Then, get down on the ground and have a closer look. First thing to do is to grab a handful of grass and try to pull it up. Healthy grass will not budge, being held in place by the roots. Grass subjected to a grub attack will come away easily, almost like a carpet. With no roots to hold the grass to the ground, the lawn will die suddenly.

Next step is to dig into the lawn and have a look to try to identify a grub. This is important as the remedy will be different to the type of grub found. In the UK you are only likely to encounter leatherjackets, chafer grubs or wireworms. In summary; wireworms are thin and orange, chafer grubs are white, usually curled up in a ‘C’ shape with a black head and leatherjackets are darker coloured, straight and can be over 2cm long.
I found a selection of leatherjackets in a lawn last year and made this short video of one of them wriggling around:

What damage can leatherjackets do to your lawn?

The damage a leatherjacket infestation can do to a lawn can be devastating

In large numbers, leatherjackets can be a very destructive lawn pest, completely destroying a lawn to such a degree that it the grass can be rolled off like a carpet! Such a severe attack is unusual, but even lighter damage can dramatically affect the look of your lawn and can lead to expensive repairs.

The best way to deal with any possible infection is to make sure that it doesn’t get out of hand. Just one or two leatherjackets in a lawn will barely be noticed, but it’s when the they appear in large numbers that you should be concerned and preventative action should be taken as soon as possible.

How can you control leatherjackets?

The only way to control a leatherjacket infection effectively is to control the grub numbers in the soil. There are a number of different methods to control them and, like most garden pests, the best control is to use several methods rather than just relying on one.

Get help from the birds! – Our feathered friends in the garden love a nice fat juicy grub for dinner, and leatherjackets are just the ticket. Unfortunately the grubs prefer to hide underground, and the birds will happily tear up your lawn to get to them. However, you can encourage them to the surface for the birds to pick off. Simply wait until a wet day (when the grubs move through the soil more easily) then lay some black plastic over the lawn overnight. When you remove it the next day the grubs will be on the surface and will be a nice breakfast for the birds.

Nemetodes! – This is a relatively new organic treatment which utilises the effect of parasitic nematode worm called Steinernema feltiae for the treatment of leatherjackets. These have to be applied carefully, at the right time and in the correct conditions, but they are a great natural remedy to these lawn pests.

Insecticide treatment – Unfortunately, effective leatherjacket insecticide treatments are expensive and difficult to find for the home-owner. However, I am licensed to apply a suitable chemical which is proven to be very effective at treating these difficult grubs, and I would be happy to discuss a Lawnscience leatherjacket lawn treatment for your lawn.

Some sources also recommend rolling your lawn to compact the soil, preventing leatherjackets from moving through it and feeding, however I strongly DO NOT recommend this for a domestic lawn, as the resulting damage caused by compacting the soil will be just as bad as a leatherjacket attack! Rolling a lawn is never recommended.

For more information and advice about your lawn, or to book a free lawn survey, please don’t hesitate to get in touch.

26 Responses to Leatherjacket grubs can destroy your lawn!

Morning Kris, I am in Manchester. We have Greenthumb who attend our lawn every few months, who confirmed that he thought we had Leatherjackets (never had them before), I had noticed that it was starting to go bald in a few of areas of the lawn, where overall, in the past, the condition of the lawn is/has been not perfect but reasonable. I dug up 3 large spadefuls of lawn (almost a full barrowful) last weekend and rummaged around and found only 3 grubs similiar to the ones further up on this page that, I would say were Leatherjackets. I tried covering part of the lawn overnight to draw them up as your article suggests, nothing. Greenthumb wants to treat them with a spray, which is fine,but is this necessary given the lifespan of these creatures, I mean have they finished their “thing” now, because we were thinking seriously of having a new lawn, that would be dug out a few inches into the soil anyway? Thanks for your help,

Hi Paul,
You should only spray an insecticide once you have positively identified the pest you are treating. If you have only found one or two, then it may not be worth treating and there maybe some other cause to the browning of your lawn.
This winter has been quite wet and I have seen a lot of lawns turning yellow just through lack of nutrients.
Hope this helps, Thanks for reading!
Kris

Hi Kris, thanks for the reply, we have no browning or yellowing of the turf, parts of the lawn are now large patches of soil (like your picture above), the grubs we dug up were leatherjackets. Do you think it would be safe to re-turf/re-seed the area without treating? thanks,

Help. My beautiful lawn that was the nicest on the street now looks like straw. The dead areas have spread and when it rains, there are noticeable exit holes through the dead grass. Are these leather jacket larvae? I’m in a new build house.

Dear Kris, I have read all the postings on this forum. We currently use a lawn care company. A couple of years ago they told us they suspected leather jackets were spoiling our lawn. The company wanted £35 on top of our regular £35 per quarter to treat them. They did the ‘plastic sheet test’ but that was inconclusive. They also suggested the possibility that the lawn was water-starved. We aerated the lawn (with detergent mixed) and the lawn greened up beautifully. This year we had to remove some turf and found underneath…. leather jackets!! Not a dense population, but approximately 2 or 3 per square yard. Is there a method of treatment that would come in cheaper than the £35 my lawn care specialists would charge?

Hi Mr. Clark,
Leatherjacket treatments cannot be bought over the counter any more so there is no “cheap alternative”.
£35 for treating what sounds like a sizeable lawn, with a licensed product by a trained professional sounds about right.
Thanks for reading.
Kris

Hi, I have recently moved to a new build property and there are many people being affected by leather jackets. My lawn appears to be in good shape at the moment. There are a lot of crane flies about. How do I make sure it doesn’t happen to mine?

My lawn started to die back around the edges from the end of last year… I tried just reseeding but the birds were helping themselves to too much of the seed. So today I dug up a section to return and found a number of these leatherjackets… I am now worried the turf I have laid will not take.
I live in Worcestershire.
How can I get rid of them and get my lawn back?
Thanks,
Nick

We are in the midst of a huge infestation that has killed the entire lawn. As we live in a new build property the house builder is treating. He has killed all the grubs with pesticide but is now suggesting re-seeding. I would rather dig up and re turf with good quality turf. Which is the best approach? How long approx would re-seeding take to establish?

I always recommend re-seeding rather than re-turfing. Not only is it much cheaper, you can also choose the best grass for your lawn and it will grow into into a much stronger, healthier lawn.
A little bit of patience is needed, but you will be rewarded.

Hi , I have leatherjackets in the backgarden, it was wet lastnight and I swept about 200 up off the patio, ive read so many differant reamdies, just need to know the BEST way to get rid of them for good, I have a dog and 2 young girls that uses the garden aswell, please help.

We laid some new turf last October and since then we have had a problem with what we believed to be fusarium. Over the winter the grass has just slowly died which we put down to the fusarium. Today we went to seed the grass in the hope that we may get some grass before the summer but found that there were leatherjackets all over the place. The turf that we laid will come up quite easily due to the fact that the roots are dead/eaten so in your opinion, would we be better to take the turf up and throw it away and then treat the leatherjackets? We also have a 4 year old and two cats and have read that some treatments can be very toxic to humans and animals.

Hi Kris, my mother’s lawn has been severely infested by leatherjackets and she has virtually lost the lawn. She has had the leatherjackets all killed by a professional company. My question is that she lives in a small clued sac, and whilst her front and back lawns are destroyed, her neighbours look untouched, how can this be? Thanks in advance, Martin.

Hi Martin,
This is quite common. An individual crane fly can lay up to 300 eggs in one lawn, so you only need one or two individuals to find the lawn for it to be completely devastated the following spring, and the neighbours lawns to be seemingly completely untouched.
It is a shame, but that’s how nature works I’m afraid!
Thanks for reading.
Kris

Hi,
I have just taken over at this golf course and have had reports of a massive hatch of daddy long legs in August leaving behind the schucks of the hatch. I have noticed some small yellow patches but can this damage be so soon after egg laying ? If there has been a large hatch and no damage was visible during the last growing year could I assume that it was not as bad as reported and does the black bin bag trick work over one night as you can appreciate I can’t leave black bins bags all over the course thanks in advance by the way our course is run by a volunteer force we have only one paid staff member we are a rather small club giving play and pay to the older generation that cant afford big golf fees and for that matter big paid green keepers

Hi Bob,
I only cover domestic lawn maintenance as the management of the turf on a golf course is very different indeed.
I suggest you have a look at the forums over at pitchcare, as they are professional groundsmen who will be able to help you with your dilemma.
Thanks for reading
Kris

Hi Chris,I live in North Yorkshire and sem to have a problem with large mud casts in my lawn causeing ded patches.Someone has said that these are caused by leatherjackets rather than worms. How can I tell which it is?
regards Jean

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This blog is aimed towards helping gardeners in the North West of England with identifying and rectifying problems with their lawns, and will also be useful to anyone else with an interest the maintenance of a great British lawn!